Topic: Cracked the fiberglass
in Forum: C3 Body
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Tried to unscrew a stubborn bolt for the rear bumper on my '72 and somehow, ended up cracking the fiberglass just above it. The crack is about 2.5" long. Never worked with fiberglass repair before. Should I attempt it on my own, or find a body guy who knows what he's doing? Love doing my own work, but I'm leaning to taking it to someone on this. Thoughts?
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My answer is that you should get professional help in repairing the fiberglas. It is hard to work with and can be toxic. Besides, you need special tools to work on it. Perhaps Joel can gives us his 2 cents worth of info!!
Dan
Jim, gotta tell you I know exactly what you are talking about when you say the fiberglass cracked at the rear bumper. I did a complete body repair and paint this past fell. I was putting on my new rear bumpers and they looked great. Came out the next day and there fiberglass had cracked exactly as you describe. I almost cried. Tried to work with it some but then just decided that that would be my personnel mark on my car. Its kinda hidden by the bumper anyway. I would say if your getting it ready to paint make sure you try the bumpers before the paint just to make sure the bolts seat flat and dont draw into the fiberglass. Best of luck. Let us know how you make out.
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Very common problem on the Chromies.
Whether or not you should attempt a repair depends on you, and your level of skill/patience. A proper repair would mean getting to the back-side of the crack and reinforcing it first, then doing the front side for support and cosmetics. Grinding/sanding fiberglass can get dirty...and itchy. Small repairs like this aren't usually a big deal, and well within the grasp of most folks with a place to do it, and the time to do it.
I'd say if you feel comfortable with it, go for it, but if you feel better letting someone else handle it, then go that route.
Whether or not you should attempt a repair depends on you, and your level of skill/patience. A proper repair would mean getting to the back-side of the crack and reinforcing it first, then doing the front side for support and cosmetics. Grinding/sanding fiberglass can get dirty...and itchy. Small repairs like this aren't usually a big deal, and well within the grasp of most folks with a place to do it, and the time to do it.
I'd say if you feel comfortable with it, go for it, but if you feel better letting someone else handle it, then go that route.
Joel Adams
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You will need to lift the cars high enough in the rear to reach the inside of the panel, and be able to move around a bit.
First, rough up the area around the crack, about 2 inches on each side of the crack, and off the end if possible. Us something sharp and cut into the crack from the backside, but don' t go all the way through. This gives it a bit more surface area for adhesion and extra strength. Don't make it smooth, leave the area a bit rough. Again, this will give byou better adhesion and a stronger repair. Make sure all old paint, primer etc. is gone.
Get a fiberglass repair kit from Autozone, O'Rileys, or other similar store. The kit will have everything you need for a small repair.
Cut at least three sections of fiberglass long and wide enough to cover the repair and leave about 2 inches all around. Cut one or two narrower strips, and shread some loose fibers.
Mix some resin with the hardener. There is enough resin in the kit to match the hardener, so judge how much to mix by matching the quanties. 1/4 resin, use 1/4 of the hardener.
Soak all of the pieces you cut in the resin, but not too long, you only have a few minutes to work or it will start to set up. Be sure the fiberglass is saturated. Put the loose fibers in the gouge you made in the backside of the crack, working it in fairly firmly with no air bubbles. The layer the 3 larger pieces, one at a time making sure they are flat against the body panel, with no air spaces.
After the larger pieces are inplace, use the narrower pieces on top. Let it dry. This will make the panel as strong as the original. If the crack is showing on the top side, you may want to put some soaked fibers, or just the resin in the crack on the outside so it can be sanded and painted if needed. Even if it won't show a bit of resin in the outside of the crack will further stregthen the area.
You may want to use a scrap hunk of fiberglass or even a board and practice a repair before actually doing the repair on the car.
Be sure to use the gloves and release compound to protect you, but DON'T get the compound on the car.
It can easily get very messy if you are not careful. But it's not too bad to do. Make sure to wear long sleeves, etc to keep fiberglass particles off of you. They itch. For days. Wear eye protection.
Have fun.
in Forum: C3 Body
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